Mains or Battery

[simon_374462703]

I am still having problems with my electrics, i am new to caravanning and am certainly struggling to come to terms with how the 2 seperate cucuits work.The only electriacl items I can get to work when not connected to the mains are the bathroom light, the fan in the kitchen and the blown air fan. When on mains the only lighting I can get to work is 2 spot lights at the front of the van and the bathroom light.

Is there a switch in caravans that swaps from 12v to mains or does everything automatically run on mains when you hook up?

I know this might sound a stupid question but if you are not told and have no information you have got to ask. I am now convinced that their is something wrong and I am considering taking the van to a dealer to be checked over.

 

[Jennifer_374461363]

There is not a change over switch, but usually a 12v switch to isolate all the 12v.

Since you have 12v to certain things it sounds like you have either some blown fuses or broken/disconnected wires.

Check the fuses first and make sure all 12v switches are on. If still not working, check the wires/connections.

 

[Jennifer_374461363]

Regarding the mains.....there will also be a main switch for that and maybe separate ones for various things. These need to be on of course. You also need to turn on the charger to charge the battery.

Do your mains sockets work?

Most vans only have 2 mains lights, older ones often have none.

Which van do you have?

 

[Robtel]

Simon,

Did you buy the caravan from a dealership or privately. Asking the seller how the electrics work might save you some time and some cash if you are thinking about taking it to a workshop. If a private sale and there is something wrong you may not get an entirely truthfull reply as the seller might think you are wanting some cash back.

Rather than take it in to a workshop do you not know a friendly electrician who could have a look over the wiring for you?

Do you have the hand book or technical specification book, there is often a wiring diagram in one of them. If you don't have these try the manufacturer's website, some do downloads of old and current handbooks. If yours is not available you could try contacting customer services to see if they could supply one.

 

[Chris_374413356]

Hi Simon, without stating the obvious, most lights also have a switch on the actual light as well as another light switch, you could also check the bulbs.

 

[simon_374462703]

I have managed to get hold of a manual.

On the power supply unit there is a neon light that is lit up, the manual states that this is incorrect, the remedial action would be to change polarity, but it does not state how?

Does anybody know?

 

[Guest]

It is possible the mains lead has had the wires changed if for example the previous owner had been in France. You may want to open up each connector and check the blue and brown leads are correctly attached. You can also buy a polarity checker from an accessory shop that plugs into a 3 pin socket. It will tell you if there is a problem in that area. If it is fine then something else is giving the false message. The circuits inside the van should not be touched as they are set, unless someone has mucked about with them.

The thing is that even if the polarity was wrong the lights should all still work correctly as the live and return are basically the same, it is only the fact that the live has a fuse in it and 'feeds' the circuit for safety that defines the difference.

I cannot speak for every caravan but most have the 12 volt circuit fed either from the mains input through a step down transformer/charger/battery in the distribution box usually under a seat, or directly from the car through the tow leads. Swopping is usually done automatically by a gizmo in the said transformer/charger box of tricks. Your spot lights are 12 volt so if they work when on mains then there is power going through the system.

I assume you have looked at the RCD box. This is where the mains enters the van and usually has 1 or 2 fused circuits. It could be 1 has tripped. There may also be a reset button that llows the system to reset to normal. You also do not mention if the fridge is working on mains, if not then there is a fault somewhere but could be just as simple as a fuse.

You also do not mention the make of van, maybe if you do someone with a similar van can help more directly.

 

[simon_374462703]

Thanks for all the info.

I have found the fault on the lighting, after tracing the wiring I found a damaged cable that when "waggled" turned the lighting on.

The polarity turned out to be a red herring.

Thanks again for your input.